TABLE 4

Cosynthesis assays in liquid SA mediuma

Cosynthesis assayaStrain (gene mutated)bClavulanic acid bioassay resultc
DonorReceptor
1S. clavuligerus ΔoppA2::acc (oppA2)S. clavuligerus pyc::aph (ceaS)++++
2S. clavuligerus ΔoppA2::acc (oppA2)S. clavuligerus RFL35 (bls2)++++
3S. clavuligerus ΔoppA2::acc (oppA2)S. clavuligerus orf14::aph−−−−−
4S. clavuligerus ΔoppA2::acc (oppA2)S. clavuligerus cyp::aph (cyp)−−−−−
5S. clavuligerus ΔoppA2::acc (oppA2)S. clavuligerus oppA1::aph (oppA1)−−−−−
6S. clavuligerus cyp::aph (cyp)S. clavuligerus pyc::aph (ceaS)−−−−−
7S. clavuligerus cyp::aph (cyp)S. clavuligerus RFL35 (bls2)−−−−−
8S. clavuligerus pyc::aph (ceaS)S. clavuligerus ΔoppA2::acc (oppA2)−−−−−
9S. clavuligerus RFL35 (bls2)S. clavuligerus ΔoppA2::acc (oppA2)−−−−−
  • a Assays 1 to 5 were also carried out using mixed cultures of both strains. The complementation results in the bioassay were identical.

  • b Donor strains were from spent sterile supernatants; receptor strains were from growing cultures.

  • c ++++, positive cosynthesis; −−−−−, negative cosynthesis. CA bioassays of each separated strain were always negative. None of the strains shown in this table produces clavulanic acid by itself. All the strains produced cephamycin C.